A functional polo shirt is a staple for racket sports and works just as well for outdoor activities and other sports. A functional polo shirt is a staple for racket sports and works just as well for outdoor activities and other sports. It’s made of 100% recycled polyester and quick drying, perfect for when you work up a sweat or on hot days. It has a three-button collar and a discreet Tenson logo on the left side of the chest.